Modelling gravity waves in an aluminium reduction cell using OpenFoam

摘要

In recent years extensive computer modelling work has tried to establish whether using a profiled cathode surface modifies the MHD stability of an aluminium reduction cell. Two types of studies have been carried out: full 3D steady-state analysis, and shallow layer 2D transient analysis. Neither type of analysis is well suited to examine the effect of a profiled cathode surface on the cell stability. The present work proposes a new method to model relative MHD stability. Lateral gravity waves were simulated in a 3D lateral slice of an aluminium reduction cell. The model was solved by using the VOF formulation of the OpenFoam code. Results of the evolution of the bath-metal interface are presented for a reduction cell having different types of irregularity on the cathode surfaces. That interface evolution is compared to the flat cathode surface case; irregular surfaces provided little extra damping of the gravity waves.